Bilateral peripheral facial nerve palsy: a rare clinical picture

Introduction: Bilateral peripheral facial palsy (BPFP) is a rare clinical entity often associated with systemic, infectious, or neurological diseases. Case report: We present a 65-year-old male who developed a severe (House-Brackmann Scale grade VI) sequential BPFP within two weeks, accompanied by hoarseness. His history was remarkable for Crohn’s disease in remission, a remote history of relapsing thrombotic thrombocytopenic purpura (TTP), nephrectomy for renal cell carcinoma and currently type 2 diabetes mellitus on insulin. Upon presentation, magnetic resonance imaging of the brain showed contrast enhancement of the facial nerves bilaterally, corresponding to a neuritis facialis, without any signs of stroke or demyelination. The basic laboratory blood tests as well as the cerebrospinal fluid analysis was unremarkable. Extensive laboratory testing showed no signs of infectious and autoimmune causes (Lyme disease, herpes infections, Epstein-Barr virus, human immunodeficiency virus) and no clinical signs of vasculitis, Guillain-Barré syndrome, sarcoidosis, a relapse of TTP or malignancy. Treatment with prednisolone (1 mg/kg body weight) led to clinical improvement (three weeks later House-Brackmann Scale II). The hoarseness disappeared after about three weeks. Conclusions: BPFP is a rare condition requiring a broad differential diagnosis and systematic evaluation. In this patient, type 2 diabetes represented a recognized risk factor, while concomitant hoarseness suggested a possible viral aetiology. Although an association of BPFP with prior TTP has not been reported and with Crohn’s disease is exceptional, a shared pathophysiological mechanism cannot be excluded.